Longitudinal study of t‐cell somatic mutations conferring glycosylphosphatidylinositol‐anchor deficiency in gulf war I veterans exposed to depleted uranium

Abstract

Fifty Veterans of the first Gulf War in 1991 exposed to depleted uranium (DU) were studied for glycosylphosphatidylinositol‐anchor (GPIa) deficient T‐cell mutants on three occasions during the years 2009, 2011, and 2013. GPIa deficiency was determined in two ways: cloning assays employing aerolysin selection and cytometry using the FLAER reagent for positive staining of GPIa cell surface proteins. Subsequent molecular analyses of deficient isolates recovered from cloning assays (Nicklas JA et al. [2019]: Environ Mol Mutagen) revealed apparent incomplete selection in some cloning assays, necessitating correction of original data to afford a more realistic estimate of GPIa deficient mutant frequency (MF) values. GPIa deficient variant frequencies (VFs) determined by cytometry were determined in the years 2011 and 2013. A positive but nonsignificant association was observed between MF and VF values determined on the same blood samples during 2013. Exposure to DU had no effect on either GPIa deficient MF or VFs. Environ. Mol. Mutagen. 60:494–504, 2019. © 2019 Wiley Periodicals, Inc.

Molecular analysis of glycosylphosphatidylinositol anchor deficient aerolysin resistant isolates in gulf war i veterans exposed to depleted uranium

“…Fifty‐two Gulf War I Veterans who were victims of “friendly fire” involving DU‐armored tanks and munitions and who participated in the biennial medical surveillance program at the Baltimore VAMC in 2007, 2009, 2011, and 2013 had blood samples taken for assays for GPIa deficiency. (Results of the 2007 study are not included in Albertini et al [] as only a few Veterans were studied that year.) The surveillance protocol was conducted in accordance with institutional human subjects' review requirements, and each participant completed an informed consent document.…”

“…Aerolysin resistant isolates were obtained as described in McDiarmid et al () and Albertini et al (). Briefly, peripheral blood mononuclear cells isolated from venous blood were plated at 2 × 10 4 cells per well with 1 × 10 4 TK6 feeder cells, 3 × 10 4 CD3/CD28 Dynabeads (Dynal Biotech no.…”

“…As described in Albertini et al (2019), we performed assays for glycosylphosphatidylinositol anchor (GPIa) deficiency measuring the frequencies of aerolysin resistant (GPIa negative) isolates that arose in vivo in T-lymphocytes. GPIa link a number of proteins to the cell membrane and the assemblage pathway consists of 26 different proteins (Nishimura et al, 1999;Paulick and Bertozzi, 2008).…”

“…Aerolysin resistance frequency studies in 50 of the Veterans and their relationship to uranium exposure is reported in Albertini et al (2019). In this article, results of molecular analyses of 862 aerolysin resistant isolates isolated from 120 assays for GPIa deficiency from 52 Veterans are described, and the frequencies of the various types of PIGA mutations are presented.…”

“…A single T-cell clone should have a unique rearrangement of one (or two) of the TCR beta genes; a greater number of rearrangements in an isolate indicates multi-clonality (Nicklas et al, 1986). As described in Albertini et al (2019), a number of the isolates had more than two TCR beta gene rearrangements, a finding incompatible with the cell of origin being a rare mutant that explains the inability to determine a PIGA mutation. However, 43 of the isolates lacking an identifiable mutation in the PIGA gene had only a single TCR rearrangement suggesting their origin from a rare mutant cell.…”